Horizontally expandable, silage storage bags are commonly used as an alternative to permanent feed storage structures such as barns and silos. From an economic standpoint, the expandable storage bag is preferable to a more elaborate, permanent structure. Further, the expandable bags are more easily loaded than permanent structures and the silage stored therein is readily accessible for use.
An exemplary prior art structure is disclosed in Reissue U.S. Pat. No. 31,810 to Lee. A tractor-powered loading apparatus is disclosed in association with an expandable bag. A backstop is located at the filled end of the bag and has attached thereto laterally spaced cables which extend back to rotatable cable drums. The drums are yieldably braked and, under a predetermined force applied to the cables, release the cable to allow movement of the loading apparatus and tractor away from the filled end of the bag. The bag is filled by a toothed rotor which propels silage through the bag inlet. By presetting the brake structure to yield at a desired cable tension, an operator can select the degree of compaction of silage in the bag.
One drawback with the prior art is that rotor structure, such as shown in Lee, is inefficient. In a conventional apparatus, a rotor body carries a plurality of axially-spaced blades or teeth. The planes of the teeth run parallel to the direction of rotation of the rotor. Consequently, only the leading edges of the teeth engage and propel the silage. To effectively move the silage, the teeth must be placed close together. This requires the provision of a substantial number of teeth, which adds to the weight and cost of manufacturing the rotor. Even with the teeth closely spaced, with silage that is dry and fine, movement of the silage through the rotor may be ineffective.
In applicant's earlier U.S. Pat. No. 4,688,480, an improved pushing plate or tooth cap was described for use on each of the teeth on the rotors. The instant invention relates to an improved means for quickly and easily mounting the caps or pusher plates on the rotor teeth with the same also being easily removable therefrom when the caps become worn.